Girl avoids eye contact becuase she likes me or doesn't want to lead me on?

In college, this girl has same major/same classes. At first I wasn't interested cause I thought she was taken and I don't know she still might be but she's shown some signs of liking me, hasn't mentioned a boyfriend yet but avoids eye contact. For instance in class one day we started talking about our majors, a class we both wanted to take over the summer and stuff like that. Then after I saw her randomly, next class she says to me "hey were you at the store yesterday? I saw you and was like 'hey I think that's (my name)'". Thing is I never told her my name, so her knowing/remembering it from the teacher saying it or whatever kinda took me by surprise. Now she'll talk to me at the beginning of class, laugh at all my jokes and all that jazz but unless we're directly talking she never looks into my eyes. Its like 3 strait hours of class, we sit opposite each other and though when I look at her she'll look in my general direction a lot it is usually 'past me' or like she's looking at something on the wall next to me, not at me. Why would a girl intentionally avoid eye contact like that? Most girls in my experience always make it a point to give eye contact at least a little to show interest or make it a point to not care about it and she doesn't seem too shy in class either so idk...